The US army has, for the first time, shot down an artillery shell in flight using a high-powered laser weapon.

Tactical high energy lasers have the capacity to change the face of the battlefield

US Army Lt Gen Joseph Cosumano

The weapon system tracked and locked on to the shell, before firing a beam of light at the projectile and hitting it.

The US Army's Space and Missile Defence Command said that "seconds later, at a point well short of its intended destination, the projectile was destroyed".

The Mobile Tactical High Energy Laser (MTHEL) is being developed by the TRW Corporation for use by the US military and the Israeli Defence Ministry.

Two years ago, it successfully shot down a Katyusha rocket, but in Monday's test it managed to destroy a shell moving at a higher speed.

The test took place at the White Sands missile range in New Mexico.

Potent weapon

A laser is a device that produces and amplifies light of a particular wavelength, or colour, which is then directed at a target with great accuracy.

If the laser is powerful enough, it can generate very high temperatures on the spot on which the light falls, melting or vaporising the target.

Military scientists are trying to develop lasers and tracking systems that can follow and hit fast-moving objects at distances ranging from tens of kilometres to, in theory, thousands of kilometres.

"This shoot-down shifts the paradigm for defensive capabilities," Lieutenant General Joseph Cosumano, head of the missile defence command, said of the latest test.

"We have shown that even an artillery projectile hurtling through the air at supersonic speed is no match for a laser."

Israeli interest

The laser was built as a joint project between the US and Israel.

The Israeli Government is interested in the system because Katyusha rockets are used by militant Islamic groups in attacks on Israel.

The system stems in part from a commitment former US President Bill Clinton made in April 1996 to then Israeli Prime Minister Shimon Peres to aid Israel in developing a security system against rockets.

Lasers were behind the space-based missile defence shield idea, labelled "Star Wars", first suggested by US President Ronald Reagan in 1983.

The Pentagon has been working on a variety of other laser weapon technologies that could be used to shoot down ballistic missiles in flight, although deployment of such weapons is at least a decade away.